Settings Editor Example¶
The Settings Editor example shows how Qt’s standard settings support is used in an application by providing an editor that enables the user to view the settings for installed applications, and modify those that can be edited.
# Copyright (C) 2013 Riverbank Computing Limited.
# Copyright (C) 2022 The Qt Company Ltd.
# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
from __future__ import annotations
"""PySide6 port of the widgets/tools/settingseditor example from Qt v5.x"""
import sys
from PySide6.QtCore import (QByteArray, QDate, QDateTime, QDir, QEvent, QPoint,
QRect, QRegularExpression, QSettings, QSize, QTime,
QTimer, Qt, Slot)
from PySide6.QtGui import (QAction, QColor, QIcon, QIntValidator,
QDoubleValidator, QRegularExpressionValidator,
QValidator)
from PySide6.QtWidgets import (QAbstractItemView, QApplication,
QCheckBox, QComboBox, QFileDialog, QDialog,
QDialogButtonBox, QGridLayout,
QGroupBox, QHeaderView, QInputDialog,
QItemDelegate, QLabel, QLineEdit,
QMainWindow, QMessageBox, QStyle, QSpinBox,
QStyleOptionViewItem, QTableWidget,
QTableWidgetItem, QTreeWidget, QTreeWidgetItem,
QVBoxLayout)
class TypeChecker:
def __init__(self, parent=None):
self.bool_exp = QRegularExpression('^(true)|(false)$')
assert self.bool_exp.isValid()
self.bool_exp.setPatternOptions(QRegularExpression.CaseInsensitiveOption)
self.byteArray_exp = QRegularExpression(r'^[\x00-\xff]*$')
assert self.byteArray_exp.isValid()
self.char_exp = QRegularExpression('^.$')
assert self.char_exp.isValid()
pattern = r'^[+-]?\d+$'
self.int_exp = QRegularExpression(pattern)
assert self.int_exp.isValid()
pattern = r'^\(([0-9]*),([0-9]*),([0-9]*),([0-9]*)\)$'
self.color_exp = QRegularExpression(pattern)
assert self.color_exp.isValid()
pattern = r'^\((-?[0-9]*),(-?[0-9]*)\)$'
self.point_exp = QRegularExpression(pattern)
assert self.point_exp.isValid()
pattern = r'^\((-?[0-9]*),(-?[0-9]*),(-?[0-9]*),(-?[0-9]*)\)$'
self.rect_exp = QRegularExpression(pattern)
assert self.rect_exp.isValid()
self.size_exp = QRegularExpression(self.point_exp)
date_pattern = '([0-9]{,4})-([0-9]{,2})-([0-9]{,2})'
self.date_exp = QRegularExpression(f'^{date_pattern}$')
assert self.date_exp.isValid()
time_pattern = '([0-9]{,2}):([0-9]{,2}):([0-9]{,2})'
self.time_exp = QRegularExpression(f'^{time_pattern}$')
assert self.time_exp.isValid()
pattern = f'^{date_pattern}T{time_pattern}$'
self.dateTime_exp = QRegularExpression(pattern)
assert self.dateTime_exp.isValid()
def type_from_text(self, text):
if self.bool_exp.match(text).hasMatch():
return bool
if self.int_exp.match(text).hasMatch():
return int
return None
def create_validator(self, value, parent):
if isinstance(value, bool):
return QRegularExpressionValidator(self.bool_exp, parent)
if isinstance(value, float):
return QDoubleValidator(parent)
if isinstance(value, int):
return QIntValidator(parent)
if isinstance(value, QByteArray):
return QRegularExpressionValidator(self.byteArray_exp, parent)
if isinstance(value, QColor):
return QRegularExpressionValidator(self.color_exp, parent)
if isinstance(value, QDate):
return QRegularExpressionValidator(self.date_exp, parent)
if isinstance(value, QDateTime):
return QRegularExpressionValidator(self.dateTime_exp, parent)
if isinstance(value, QTime):
return QRegularExpressionValidator(self.time_exp, parent)
if isinstance(value, QPoint):
return QRegularExpressionValidator(self.point_exp, parent)
if isinstance(value, QRect):
return QRegularExpressionValidator(self.rect_exp, parent)
if isinstance(value, QSize):
return QRegularExpressionValidator(self.size_exp, parent)
return None
def from_string(self, text, original_value):
if isinstance(original_value, QColor):
match = self.color_exp.match(text)
return QColor(min(int(match.captured(1)), 255),
min(int(match.captured(2)), 255),
min(int(match.captured(3)), 255),
min(int(match.captured(4)), 255))
if isinstance(original_value, QDate):
value = QDate.fromString(text, Qt.ISODate)
return value if value.isValid() else None
if isinstance(original_value, QDateTime):
value = QDateTime.fromString(text, Qt.ISODate)
return value if value.isValid() else None
if isinstance(original_value, QTime):
value = QTime.fromString(text, Qt.ISODate)
return value if value.isValid() else None
if isinstance(original_value, QPoint):
match = self.point_exp.match(text)
return QPoint(int(match.captured(1)),
int(match.captured(2)))
if isinstance(original_value, QRect):
match = self.rect_exp.match(text)
return QRect(int(match.captured(1)),
int(match.captured(2)),
int(match.captured(3)),
int(match.captured(4)))
if isinstance(original_value, QSize):
match = self.size_exp.match(text)
return QSize(int(match.captured(1)),
int(match.captured(2)))
if isinstance(original_value, list):
return text.split(',')
return type(original_value)(text)
class MainWindow(QMainWindow):
def __init__(self, parent=None):
super().__init__(parent)
self.settings_tree = SettingsTree()
self.setCentralWidget(self.settings_tree)
self.location_dialog = None
self.create_actions()
self.create_menus()
self.auto_refresh_action.setChecked(True)
self.fallbacks_action.setChecked(True)
self.setWindowTitle("Settings Editor")
self.resize(500, 600)
@Slot()
def open_settings(self):
if self.location_dialog is None:
self.location_dialog = LocationDialog(self)
if self.location_dialog.exec():
settings = QSettings(self.location_dialog.format(),
self.location_dialog.scope(),
self.location_dialog.organization(),
self.location_dialog.application())
self.set_settings_object(settings)
self.fallbacks_action.setEnabled(True)
@Slot()
def open_inifile(self):
file_name, _ = QFileDialog.getOpenFileName(self, "Open INI File",
'', "INI Files (*.ini *.conf)")
if file_name:
self.load_ini_file(file_name)
def load_ini_file(self, file_name):
settings = QSettings(file_name, QSettings.IniFormat)
if settings.status() != QSettings.NoError:
return
self.set_settings_object(settings)
self.fallbacks_action.setEnabled(False)
@Slot()
def open_property_list(self):
file_name, _ = QFileDialog.getOpenFileName(self,
"Open Property List", '',
"Property List Files (*.plist)")
if file_name:
settings = QSettings(file_name, QSettings.NativeFormat)
self.set_settings_object(settings)
self.fallbacks_action.setEnabled(False)
@Slot()
def open_registry_path(self):
path, ok = QInputDialog.getText(self, "Open Registry Path",
"Enter the path in the Windows registry:",
QLineEdit.Normal, 'HKEY_CURRENT_USER\\')
if ok and path != '':
settings = QSettings(path, QSettings.NativeFormat)
self.set_settings_object(settings)
self.fallbacks_action.setEnabled(False)
@Slot()
def about(self):
QMessageBox.about(self, "About Settings Editor",
"The <b>Settings Editor</b> example shows how to access "
"application settings using Qt.")
def create_actions(self):
self.open_settings_action = QAction("&Open Application Settings...",
self, shortcut="Ctrl+O", triggered=self.open_settings)
self.open_ini_file_action = QAction("Open I&NI File...", self,
shortcut="Ctrl+N", triggered=self.open_inifile)
self.open_property_list_action = QAction("Open macOS &Property List...", self,
shortcut="Ctrl+P",
triggered=self.open_property_list)
if sys.platform != 'darwin':
self.open_property_list_action.setEnabled(False)
self.open_registry_path_action = QAction(
"Open Windows &Registry Path...", self, shortcut="Ctrl+G",
triggered=self.open_registry_path)
if sys.platform != 'win32':
self.open_registry_path_action.setEnabled(False)
self.refresh_action = QAction("&Refresh", self, shortcut="Ctrl+R",
enabled=False, triggered=self.settings_tree.refresh)
self.exit_action = QAction("E&xit", self, shortcut="Ctrl+Q", triggered=self.close)
self.auto_refresh_action = QAction("&Auto-Refresh", self,
shortcut="Ctrl+A", checkable=True, enabled=False)
self.auto_refresh_action.triggered[bool].connect(self.settings_tree.set_auto_refresh)
self.auto_refresh_action.triggered[bool].connect(self.refresh_action.setDisabled)
self.fallbacks_action = QAction("&Fallbacks", self,
shortcut="Ctrl+F", checkable=True, enabled=False)
self.fallbacks_action.triggered[bool].connect(self.settings_tree.set_fallbacks_enabled)
self.about_action = QAction("&About", self, triggered=self.about)
self.about_Qt_action = QAction("About &Qt", self,
triggered=qApp.aboutQt) # noqa: F821
def create_menus(self):
self.file_menu = self.menuBar().addMenu("&File")
self.file_menu.addAction(self.open_settings_action)
self.file_menu.addAction(self.open_ini_file_action)
self.file_menu.addAction(self.open_property_list_action)
self.file_menu.addAction(self.open_registry_path_action)
self.file_menu.addSeparator()
self.file_menu.addAction(self.refresh_action)
self.file_menu.addSeparator()
self.file_menu.addAction(self.exit_action)
self.options_menu = self.menuBar().addMenu("&Options")
self.options_menu.addAction(self.auto_refresh_action)
self.options_menu.addAction(self.fallbacks_action)
self.menuBar().addSeparator()
self.help_menu = self.menuBar().addMenu("&Help")
self.help_menu.addAction(self.about_action)
self.help_menu.addAction(self.about_Qt_action)
def set_settings_object(self, settings):
settings.setFallbacksEnabled(self.fallbacks_action.isChecked())
self.settings_tree.set_settings_object(settings)
self.refresh_action.setEnabled(True)
self.auto_refresh_action.setEnabled(True)
nice_name = QDir.fromNativeSeparators(settings.fileName())
nice_name = nice_name.split('/')[-1]
if not settings.isWritable():
nice_name += " (read only)"
self.setWindowTitle(f"{nice_name} - Settings Editor")
class LocationDialog(QDialog):
def __init__(self, parent=None):
super().__init__(parent)
self.format_combo = QComboBox()
self.format_combo.addItem("Native")
self.format_combo.addItem("INI")
self.scope_cCombo = QComboBox()
self.scope_cCombo.addItem("User")
self.scope_cCombo.addItem("System")
self.organization_combo = QComboBox()
self.organization_combo.addItem("Trolltech")
self.organization_combo.setEditable(True)
self.application_combo = QComboBox()
self.application_combo.addItem("Any")
self.application_combo.addItem("Application Example")
self.application_combo.addItem("Assistant")
self.application_combo.addItem("Designer")
self.application_combo.addItem("Linguist")
self.application_combo.setEditable(True)
self.application_combo.setCurrentIndex(3)
format_label = QLabel("&Format:")
format_label.setBuddy(self.format_combo)
scope_label = QLabel("&Scope:")
scope_label.setBuddy(self.scope_cCombo)
organization_label = QLabel("&Organization:")
organization_label.setBuddy(self.organization_combo)
application_label = QLabel("&Application:")
application_label.setBuddy(self.application_combo)
self.locations_groupbox = QGroupBox("Setting Locations")
self.locations_table = QTableWidget()
self.locations_table.setSelectionMode(QAbstractItemView.SingleSelection)
self.locations_table.setSelectionBehavior(QAbstractItemView.SelectRows)
self.locations_table.setEditTriggers(QAbstractItemView.NoEditTriggers)
self.locations_table.setColumnCount(2)
self.locations_table.setHorizontalHeaderLabels(("Location", "Access"))
self.locations_table.horizontalHeader().setSectionResizeMode(0, QHeaderView.Stretch)
self.locations_table.horizontalHeader().resizeSection(1, 180)
self.button_box = QDialogButtonBox(QDialogButtonBox.Ok | QDialogButtonBox.Cancel)
self.format_combo.activated.connect(self.update_locations)
self.scope_cCombo.activated.connect(self.update_locations)
self.organization_combo.lineEdit().editingFinished.connect(self.update_locations)
self.application_combo.lineEdit().editingFinished.connect(self.update_locations)
self.button_box.accepted.connect(self.accept)
self.button_box.rejected.connect(self.reject)
locations_layout = QVBoxLayout(self.locations_groupbox)
locations_layout.addWidget(self.locations_table)
main_layout = QGridLayout(self)
main_layout.addWidget(format_label, 0, 0)
main_layout.addWidget(self.format_combo, 0, 1)
main_layout.addWidget(scope_label, 1, 0)
main_layout.addWidget(self.scope_cCombo, 1, 1)
main_layout.addWidget(organization_label, 2, 0)
main_layout.addWidget(self.organization_combo, 2, 1)
main_layout.addWidget(application_label, 3, 0)
main_layout.addWidget(self.application_combo, 3, 1)
main_layout.addWidget(self.locations_groupbox, 4, 0, 1, 2)
main_layout.addWidget(self.button_box, 5, 0, 1, 2)
self.update_locations()
self.setWindowTitle("Open Application Settings")
self.resize(650, 400)
def format(self):
if self.format_combo.currentIndex() == 0:
return QSettings.NativeFormat
else:
return QSettings.IniFormat
def scope(self):
if self.scope_cCombo.currentIndex() == 0:
return QSettings.UserScope
else:
return QSettings.SystemScope
def organization(self):
return self.organization_combo.currentText()
def application(self):
if self.application_combo.currentText() == "Any":
return ''
return self.application_combo.currentText()
def update_locations(self):
self.locations_table.setUpdatesEnabled(False)
self.locations_table.setRowCount(0)
for i in range(2):
if i == 0:
if self.scope() == QSettings.SystemScope:
continue
actual_scope = QSettings.UserScope
else:
actual_scope = QSettings.SystemScope
for j in range(2):
if j == 0:
if not self.application():
continue
actual_application = self.application()
else:
actual_application = ''
settings = QSettings(self.format(), actual_scope,
self.organization(), actual_application)
row = self.locations_table.rowCount()
self.locations_table.setRowCount(row + 1)
item0 = QTableWidgetItem()
item0.setText(settings.fileName())
item1 = QTableWidgetItem()
disable = not (settings.childKeys() or settings.childGroups())
if row == 0:
if settings.isWritable():
item1.setText("Read-write")
disable = False
else:
item1.setText("Read-only")
self.button_box.button(QDialogButtonBox.Ok).setDisabled(disable)
else:
item1.setText("Read-only fallback")
if disable:
item0.setFlags(item0.flags() & ~Qt.ItemIsEnabled)
item1.setFlags(item1.flags() & ~Qt.ItemIsEnabled)
self.locations_table.setItem(row, 0, item0)
self.locations_table.setItem(row, 1, item1)
self.locations_table.setUpdatesEnabled(True)
class SettingsTree(QTreeWidget):
def __init__(self, parent=None):
super().__init__(parent)
self._type_checker = TypeChecker()
self.setItemDelegate(VariantDelegate(self._type_checker, self))
self.setHeaderLabels(("Setting", "Type", "Value"))
self.header().setSectionResizeMode(0, QHeaderView.Stretch)
self.header().setSectionResizeMode(2, QHeaderView.Stretch)
self.settings = None
self.refresh_timer = QTimer()
self.refresh_timer.setInterval(2000)
self.auto_refresh = False
self.group_icon = QIcon()
style = self.style()
self.group_icon.addPixmap(style.standardPixmap(QStyle.SP_DirClosedIcon),
QIcon.Normal, QIcon.Off)
self.group_icon.addPixmap(style.standardPixmap(QStyle.SP_DirOpenIcon),
QIcon.Normal, QIcon.On)
self.key_icon = QIcon()
self.key_icon.addPixmap(style.standardPixmap(QStyle.SP_FileIcon))
self.refresh_timer.timeout.connect(self.maybe_refresh)
def set_settings_object(self, settings):
self.settings = settings
self.clear()
if self.settings is not None:
self.settings.setParent(self)
self.refresh()
if self.auto_refresh:
self.refresh_timer.start()
else:
self.refresh_timer.stop()
def sizeHint(self):
return QSize(800, 600)
@Slot(bool)
def set_auto_refresh(self, autoRefresh):
self.auto_refresh = autoRefresh
if self.settings is not None:
if self.auto_refresh:
self.maybe_refresh()
self.refresh_timer.start()
else:
self.refresh_timer.stop()
@Slot(bool)
def set_fallbacks_enabled(self, enabled):
if self.settings is not None:
self.settings.setFallbacksEnabled(enabled)
self.refresh()
@Slot()
def maybe_refresh(self):
if self.state() != QAbstractItemView.EditingState:
self.refresh()
@Slot()
def refresh(self):
if self.settings is None:
return
# The signal might not be connected.
try:
self.itemChanged.disconnect(self.update_setting)
except Exception:
pass
self.settings.sync()
self.update_child_items(None)
self.itemChanged.connect(self.update_setting)
def event(self, event):
if event.type() == QEvent.WindowActivate:
if self.isActiveWindow() and self.auto_refresh:
self.maybe_refresh()
return super(SettingsTree, self).event(event)
def update_setting(self, item):
key = item.text(0)
ancestor = item.parent()
while ancestor:
key = ancestor.text(0) + '/' + key
ancestor = ancestor.parent()
self.settings.setValue(key, item.data(2, Qt.ItemDataRole.UserRole))
if self.auto_refresh:
self.refresh()
def update_child_items(self, parent):
divider_index = 0
for group in self.settings.childGroups():
child_index = self.find_child(parent, group, divider_index)
if child_index != -1:
child = self.child_at(parent, child_index)
child.setText(1, '')
child.setText(2, '')
child.setData(2, Qt.ItemDataRole.UserRole, None)
self.move_item_forward(parent, child_index, divider_index)
else:
child = self.create_item(group, parent, divider_index)
child.setIcon(0, self.group_icon)
divider_index += 1
self.settings.beginGroup(group)
self.update_child_items(child)
self.settings.endGroup()
for key in self.settings.childKeys():
child_index = self.find_child(parent, key, 0)
if child_index == -1 or child_index >= divider_index:
if child_index != -1:
child = self.child_at(parent, child_index)
for i in range(child.childCount()):
self.delete_item(child, i)
self.move_item_forward(parent, child_index, divider_index)
else:
child = self.create_item(key, parent, divider_index)
child.setIcon(0, self.key_icon)
divider_index += 1
else:
child = self.child_at(parent, child_index)
value = self.settings.value(key)
if value is None:
child.setText(1, 'Invalid')
else:
# Try to convert to type unless a QByteArray is received
if isinstance(value, str):
value_type = self._type_checker.type_from_text(value)
if value_type:
value = self.settings.value(key, type=value_type)
child.setText(1, value.__class__.__name__)
child.setText(2, VariantDelegate.display_text(value))
child.setData(2, Qt.ItemDataRole.UserRole, value)
while divider_index < self.child_count(parent):
self.delete_item(parent, divider_index)
def create_item(self, text, parent, index):
after = None
if index != 0:
after = self.child_at(parent, index - 1)
if parent is not None:
item = QTreeWidgetItem(parent, after)
else:
item = QTreeWidgetItem(self, after)
item.setText(0, text)
item.setFlags(item.flags() | Qt.ItemIsEditable)
return item
def delete_item(self, parent, index):
if parent is not None:
item = parent.takeChild(index)
else:
item = self.takeTopLevelItem(index)
del item
def child_at(self, parent, index):
if parent is not None:
return parent.child(index)
else:
return self.topLevelItem(index)
def child_count(self, parent):
if parent is not None:
return parent.childCount()
else:
return self.topLevelItemCount()
def find_child(self, parent, text, startIndex):
for i in range(self.child_count(parent)):
if self.child_at(parent, i).text(0) == text:
return i
return -1
def move_item_forward(self, parent, oldIndex, newIndex):
for int in range(oldIndex - newIndex):
self.delete_item(parent, newIndex)
class VariantDelegate(QItemDelegate):
def __init__(self, type_checker, parent=None):
super().__init__(parent)
self._type_checker = type_checker
def paint(self, painter, option, index):
if index.column() == 2:
value = index.model().data(index, Qt.ItemDataRole.UserRole)
if not self.is_supported_type(value):
my_option = QStyleOptionViewItem(option)
my_option.state &= ~QStyle.State_Enabled
super(VariantDelegate, self).paint(painter, my_option, index)
return
super(VariantDelegate, self).paint(painter, option, index)
def createEditor(self, parent, option, index):
if index.column() != 2:
return None
original_value = index.model().data(index, Qt.ItemDataRole.UserRole)
if not self.is_supported_type(original_value):
return None
editor = None
if isinstance(original_value, bool):
editor = QCheckBox(parent)
if isinstance(original_value, int):
editor = QSpinBox(parent)
editor.setRange(-32767, 32767)
else:
editor = QLineEdit(parent)
editor.setFrame(False)
validator = self._type_checker.create_validator(original_value, editor)
if validator:
editor.setValidator(validator)
return editor
def setEditorData(self, editor, index):
if not editor:
return
value = index.model().data(index, Qt.ItemDataRole.UserRole)
if isinstance(editor, QCheckBox):
editor.setCheckState(Qt.Checked if value else Qt.Unchecked)
elif isinstance(editor, QSpinBox):
editor.setValue(value)
else:
editor.setText(self.display_text(value))
def value_from_lineedit(self, lineedit, model, index):
if not lineedit.isModified():
return None
text = lineedit.text()
validator = lineedit.validator()
if validator is not None:
state, text, _ = validator.validate(text, 0)
if state != QValidator.Acceptable:
return None
original_value = index.model().data(index, Qt.ItemDataRole.UserRole)
return self._type_checker.from_string(text, original_value)
def setModelData(self, editor, model, index):
value = None
if isinstance(editor, QCheckBox):
value = editor.checkState() == Qt.Checked
elif isinstance(editor, QSpinBox):
value = editor.value()
else:
value = self.value_from_lineedit(editor, model, index)
if value is not None:
model.setData(index, value, Qt.ItemDataRole.UserRole)
model.setData(index, self.display_text(value), Qt.ItemDataRole.DisplayRole)
@staticmethod
def is_supported_type(value):
return isinstance(value, (bool, float, int, QByteArray, str, QColor,
QDate, QDateTime, QTime, QPoint, QRect,
QSize, list))
@staticmethod
def display_text(value):
if isinstance(value, str):
return value
if isinstance(value, bool):
return '✓' if value else '☐'
if isinstance(value, (int, float, QByteArray)):
return str(value)
if isinstance(value, QColor):
(r, g, b, a) = (value.red(), value.green(), value.blue(), value.alpha())
return f'({r},{g},{b},{a})'
if isinstance(value, (QDate, QDateTime, QTime)):
return value.toString(Qt.ISODate)
if isinstance(value, QPoint):
x = value.x()
y = value.y()
return f'({x},{y})'
if isinstance(value, QRect):
x = value.x()
y = value.y()
w = value.width()
h = value.height()
return f'({x},{y},{w},{h})'
if isinstance(value, QSize):
w = value.width()
h = value.height()
return f'({w},{h})'
if isinstance(value, list):
return ','.join(map(repr, value))
if value is None:
return '<Invalid>'
return f'<{value}>'
if __name__ == '__main__':
app = QApplication(sys.argv)
main_win = MainWindow()
if len(sys.argv) > 1:
main_win.load_ini_file(sys.argv[1])
main_win.show()
sys.exit(app.exec())